One known method of constructing buildings is to pour concrete in place, utilizing suitable forms, to produce poured-in-place concrete columns, beams and floor slabs. This method has the advantage of producing buildings which are strong, highly rigid, durable and highly fire resistant. However, this method requires the use of elaborate forms and temporary supports, which must be left in place for a sufficient time, often 28 days, to allow the concrete to cure until it develops adequate strength.
Another known method of constructing buildings is to assemble precast columns, beams and floor slabs. This method has the advantage of rapid erection, with little or no need for temporary supports. However, precast concrete buildings tend to be less rigid than poured-in-place concrete buildings. Moreover, the precast concrete components must be manufactured to close tolerances as to length and other dimensions, so that the precast components will fit together properly.